Chemical Engineering Commons^™

Reduced Exhaust Emissions Through Blending N-Butanol With Ultra Low Sulfur Diesel And Synthetic Paraffinic Kerosene In Reactivity Controlled Compression Ignition Combustion, Remi Gaubert

College of Graduate Studies: Theses & Dissertations

Increasing restrictions on the emitted exhaust emissions in diesel engines are becoming a more challenging task than in previous years. An electronic common rail fuel injection system and a port fuel injection (PFI) system were developed for an experimental engine to research dual fuel combustion. The experimental research was conducted at 1500 rpm and 4, 5, and 6 bar indicated mean effective pressure (IMEP). n-Butanol was port fuel injected at a 60% by mass fraction coupled with direct injection (DI) of three fuels, including ultra-low sulfur diesel (ULSD RCCI), a 50-50 wt-% blend of ULSD and butanol (ULSD-Bu RCCI), and …

The Significance Of Grouping And Missed Bubbles On Interfacial Area Concentration And Void Fraction, Chandller Stephen-Leslie Mills

Doctoral Dissertations

"The two-fluid model is used in nuclear reactor safety codes. Two of the important constitutive relations will be discussed in this study, the interfacial area concentration and void fraction. The Interfacial area concentration is directly affected by the number of bubbles and how these bubbles are categorized into groups. In this study, a new algorithm was implemented to account for trailing bubbles, bubbles with short response times, and the categorization of bubbles based upon diameter for all group 1 bubbles. The optical and conductivity probes were used to determine the void fraction and interfacial area concentration in a bubble column. …

Numerical Characterization Of The Flow Field And Heat Transfer Inside The Receiver Of A Parabolic Trough Solar Collector Carrying Supercritical Co2, Samad Gharehdaghimollahajloo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The aim of this research is to provide a detailed numerical analysis of flow field and heat transfer inside the heat collecting element of a parabolic trough collector. The parabolic trough collector is used as the boiler in a direct Super Critical Carbon Dioxide (S-CO2) Brayton cycle.

A single collector is modeled and analyzed with different inlet conditions. The working fluid is supercritical since its pressure is increased to above critical pressure in the compressor while its temperature reaches 300 °C after passing through the recuperators and before entering the solar field. For the first time, this research considers both …

Thermodynamics Of Concentrated Solid Solution Alloys, Michael C. Gao, Chuan Zhang, Pan Gao, Fan Zhang, Lizhi Ouyang, Michael Widom, Jeffrey A. Hawk

Mathematical Sciences Faculty Research

This paper reviews the three main approaches for predicting the formation of concentrated solid solution alloys (CSSA) and for modeling their thermodynamic properties, in particular, utilizing the methodologies of empirical thermo-physical parameters, CALPHAD method, and first-principles calculations combined with hybrid Monte Carlo/Molecular Dynamics (MC/MD) simulations. In order to speed up CSSA development, a variety of empirical parameters based on Hume-Rothery rules have been developed. Herein, these parameters have been systematically and critically evaluated for their efficiency in predicting solid solution formation. The phase stability of representative CSSA systems is then illustrated from the perspectives of phase diagrams and nucleation driving …

Computational Modeling Of High-Entropy Alloys: Structures, Thermodynamics And Elasticity, Michael C. Gao, Pan Gao, Jeffrey A. Hawk, Lizhi Ouyang, David E. Alman, Mike Widom

Mathematical Sciences Faculty Research

This article provides a short review on computational modeling on the formation, thermodynamics, and elasticity of single-phase high-entropy alloys (HEAs). Hundreds of predicted single-phase HEAs were re-examined using various empirical thermo-physical parameters. Potential BCC HEAs (CrMoNbTaTiVW, CrMoNbReTaTiVW, and CrFeMoNbReRuTaVW) were suggested based on CALPHAD modeling. The calculated vibrational entropies of mixing are positive for FCC CoCrFeNi, negative for BCC MoNbTaW, and near-zero for HCP CoOsReRu. The total entropies of mixing were observed to trend in descending order: CoCrFeNi > CoOsReRu > MoNbTaW. Calculated lattice parameters agree extremely well with averaged values estimated from the rule of mixtures (ROM) if the same crystal …

Energy From Chemical Reactions: Understanding The Combustion Engine, Tammy Guthrie, Kathy Prophet, Greg Herzig, Cassie Kautzer

Middle School Lesson Plans

Automobiles produce a large amount of heat generated by the burning of gasoline. Burning gasoline is a chemical reaction that causes a phase change. This is called combustible energy. During combustion fuel combines with oxygen to release energy (such as heat, light, sound) along with another product that is often considered waste. Most of the energy produced is not used to power the automobile, but is released as heat. 19.3 pounds of the greenhouse gas, carbon dioxide, is produced from the combustion of 1 gallon of U.S. gasoline according to the U.S. Energy Information Administration.

Experimental Analysis Of R134a, R22, And R404 For An Edibon Taab: Air Conditioning Lab Unit, Kyle T. Heesen

Senior Honors Projects, 2010-2019

This paper presents an experimental analysis of an Ebidon® TAABTM: Air Conditioning Lab unit running on R-134a being compared with R22 and R404 refrigerants, a $24,449 piece of equipment purchased by the JMU ISAT Department. In this paper we will compare the performance of the R-134a refrigerant under a range of working conditions and compare them to how the system would run on R22 or R404. The experimental tests use varying fan speeds and the R-134a data collected is compared to simulated data collected for R22 and R404. Analysis of the collected data and simulated data will be compared on …

Passive Solar Distillation Of Acid Rock Drainage, Stephanie Shreve, Luke Galuska, Anna Stoller, Alex Raney, Agustin Caceres, Caitlyn Chambers, Chris Graham, Devin Hazlett

Chemical Engineering Undergraduate Honors Theses

Arkansas Razorback Distillers (A.R.D.) has developed a passive solar distillation system for treating acid rock drainage (ARD) from legacy (i.e., abandoned) mines. The solar still addresses the need to reduce both the metal sulfate contaminants as well as the acidity of acid rock drainage. During the design phase, A.R.D. addressed the need for the system to be low cost, simple, and effective for general use as well as a specified location. To demonstrate the applicability of the solar still, A.R.D. used the Freeport McMoRan Inc. Copper Queen legacy mine in Bisbee, Arizona, as a base case scenario. The mine was …

Molecular Modeling Of Antibody-Antigen Binding Near Solid Surfaces, Derek Bush, Thomas Knotts

Biomedical Engineering Western Regional Conference

Antibody microarrays are biosensors that have the potential to revolutionize molecular detection in medicine, scientific research, and national defense. However, current microarrays are not widely used due to problems including poor reproducibility and signal quality, unbalanced antibody performance, and cross-reactivity. Prior work in the area focused mainly on the stability of the antibody alone and not its affinity for its antigen. This presentation shows results of using molecular simulation to determine how different types of surfaces affect antigen binding to surface-tethered antibodies. The results offer an unprecedented, molecular-level view into these protein-protein-surface interactions and how to drive binding to occur.

Hybrid Metal Oxide Cycle Water Splitting, Richard B. Diver Jr., Robert D. Palumbo, Nathan P. Siegel, James E. Miller

Other Faculty Research and Publications

Hybrid thermochemical water splitting systems are disclosed that thermally reduces metal oxides particles to displace some but not all of the electrical requirements in a water splitting electrolytic cell. In these hybrid systems, the thermal reduction temperature is significantly reduced compared to two-step metal-oxide thermochemical cycles in which only thermal energy is required to produce hydrogen from water. Also, unlike conventional higher temperature systems where the reduction step must be carried out under reduced oxygen pressure, the reduction step in the proposed hybrid systems can be carried out in air, allowing for thermal input by a solar power tower with …

Surface Chemisty Study Of Monazite Flotation In Coal Refuse Systems, Wencai Zhang

Theses and Dissertations--Mining Engineering

Rare earth mineral recovery from alternative resources such as coal and coal byproducts is increasingly important to provide an opportunity for economic recovery from U.S. sources. Currently, China produces the majority of the 149,000 tons of rare earth elements used annually worldwide of which the U.S. imports 11% or around 16,000 tons. There are no significant mining operations producing rare earth elements in the U.S. However, there are many U.S. sources containing rare earth minerals such as monazite including heavy mineral sand and phosphate operations. Monazite mineral particles of a few microns have also been detected in Fire Clay seam …

Method For Carbon Dioxide Splitting, James E. Miller, Richard B. Diver, Nathan P. Siegel

Other Faculty Research and Publications

A method for splitting carbon dioxide via a two-step metal oxide thermochemical cycle by heating a metal oxide compound selected from an iron oxide material of the general formula A_xFe_3-xO₄, where 0≦x≦1 and A is a metal selected from Mg, Cu, Zn, Ni, Co, and Mn, or a ceria oxide compound of the general formula M_aCe_bO_c, where 0

Heat Transfer Analysis In A Paddle Reactor For Biomass Fast Pyrolyis, Ankith Ullal

Dissertations, Master's Theses and Master's Reports

Heat transfer analysis was performed on a novel auger reactor for biomass fast pyrolysis. As part of this analysis, correlations for specific heat capacity and heat transfer coefficients for biomass (sawdust) and sand (used as heat transfer medium) were developed. For sand, the heat transfer coefficient followed a power law distribution with reactor fill level and temperature. For raw biomass, the heat transfer coefficient also showed similar dependence on fill level, but was independent of temperature up to 300°C. These correlations were used in a one dimensional heat transfer model developed to calculate the heating time and heating rate of …

Understanding Glycoside Hydrolase Processivity For Improved Biomass Conversion, Suvamay Jana

Theses and Dissertations--Chemical and Materials Engineering

In nature, organisms secrete synergistic enzyme cocktails to deconstruct crystalline polysaccharides, such as cellulose and chitin, to soluble sugars. The cocktails consist of multiple classes of processive and non-processive glycoside hydrolases (GH) that aid in substrate accessibility and reduce product inhibition. Processive GHs attach to chain ends and hydrolyze many glycosidic linkages in sequence to produce disaccharide units before dissociation, and as such, are responsible for the majority of hydrolytic bond cleavages. Accordingly, processive GHs are targets for activity improvements towards efficient and economical biomass conversion. However, the mechanism and factors responsible for processivity are still not understood completely at …

3d Fe Modelling Of Die Stress And Wear In Non-Isothermal Forging Of Ti–6al–4v Turbine Blade, Shiyuan Luo, Dahu Zhu, Lin Hua, Dongsheng Qian, Sijie Yan

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Modeling Pyrolysis Of Large Coal Particles With Many Species, Jianqing Li

Master's Theses (2009 -)

Coal currently supplies 40% of the world’s electricity needs, and is one of the most important energy sources. As the initial stage of coal combustion, pyrolysis is a thermal decomposition process which converts coal into light gases and tars, which are subsequently consumed in combustion reactions, as well as solid char. Recently there has been interest in using slow pyrolysis as a stand-alone process for the production of chemicals and fuels from large (mm-scale) coal particles. Simulations can be used to efficiently study the impact of pyrolysis conditions on gas, tar and char yields, as well as gas and tar …

Methanol And Dimethyl Ether From Renewable Hydrogen And Carbon Dioxide: Alternative Fuels Production And Life-Cycle Assessment, Michael J. Matzen, Yaşar Demirel

Yaşar Demirel Publications

In this work we investigate two renewably based alternative fuels; methanol and dimethyl ether. The ultimate feedstocks for production are wind-based electrolytic hydrogen and carbon dioxide captured from an ethanol fermentation process. Dimethyl ether production was modeled in ASPEN Plus using a previously simulated methanol production facility. The facilities use 18.6 metric tons (mt) of H₂ and 138.4 mt CO₂ per day. Methanol is produced at a rate 96.7 mt/day (99.5 wt%) and dimethyl ether is produced at a rate of 68.5 mt/day (99.6 wt%). A full comparative life-cycle assessment (cradle-to-grave) of both fuels was conducted to investigate …

Go With The Flow –Thermoelectric Energy, Shawn Bell

Middle School Lesson Plans

In this unit, students will learn how thermal energy be transferred and transformed. They will carry out investigations to gather evidence to support an explanation about direct conversion of heat into electrical energy. They will develop a model that shows the components of the system and changes in the system being investigated, and they will use evidence from the investigation to construct an explanation for how the energy flows.

Fluid Analysis In Solar Heat Pipes, Ben Krumholz, Michael Agavo, William Dundon

Mechanical Engineering

Evacuated tube solar collectors are efficient systems that use heat pipes to facilitate heat transfer. They use incoming solar radiation to heat water. Professor Mason Medizade tasked the team with choosing a component of the system to research and test its influence on system performance. The team investigated the working fluid that runs through the heat pipes. Distilled water, acetone, and ethanol at a range of fill volumes form 1 mL to 11 mL were tested. The team's goal was to find a volume for each fluid to maximize performance of the system. Performance was defined as average temperature rise …

Maximizing Orc Performance With Optimal Match Of Working Fluid With System Design, Kirtipal Barse, Michael Mann

Chemical Engineering Faculty Publications

This article compares constrained system design to non-constrained system design for the basic Organic Rankine Cycle (ORC). The 12 working fluids studied include eight dry-type, three isentropic, and one wet-type fluids. The ORC model was developed using Aspen HYSYS® and validated with data obtained from the literature. The constrained design compared the performance of working fluids for a fixed heat exchanger and turbine configuration. A non-constrained design was studied by altering the design specifications for the heat exchangers and turbine to match the working fluid. An energy and exergy analysis was performed using first and second law efficiency. The exergy …

Thermal Microfluidic Devices; Design, Fabrication And Applications, Benyamin Davaji

Dissertations (1934 -)

This thesis investigates the thermal actuation and temperature measurement methods in microfluidic devices. We designed and fabricated microfluidic devices with various functionalities such as: bio sensing, particle counting, microscale calorimetry, and cellular temperature measurement. All of these functionalities use thermal measurement methods. When quantitative measurements are required, the label-free nature of thermal measurement methods, along with its simple readout, make it a powerful candidate for lab on a chip and bio sensing/detection applications. In this work, thermal measurement methods are used to characterize bio-samples, measure concentrations, study thermal responses, and even perform particle cytometry. However, thermal measurement methods are known …

Thermal Transport Properties Of Dry Spun Carbon Nanotube Sheets, Heath E. Misak, James L. Rutledge, Eric D. Swenson, Shankar Mall

Faculty Publications

The thermal properties of carbon nanotube- (CNT-) sheet were explored and compared to copper in this study. The CNT-sheet was made from dry spinning CNTs into a nonwoven sheet. This nonwoven CNT-sheet has anisotropic properties in in-plane and out-of-plane directions. The in-plane direction has much higher thermal conductivity than the out-of-plane direction. The in-plane thermal conductivity was found by thermal flash analysis, and the out-of-plane thermal conductivity was found by a hot disk method. The thermal irradiative properties were examined and compared to thermal transport theory. The CNT-sheet was heated in the vacuum and the temperature was measured with an …

Effect Of Spalled Particles Thermal Degradation On A Hypersonic Flow Field Environment, Raghava S. C. Davuluri, Huaibao Zhang, Alexandre Martin

Mechanical Engineering Faculty Publications

Two-way coupling is performed between a spallation code and a hypersonic aerothermodynamics CFD solver to evaluate the effect of spalled particles on the flow field. Time accurate solutions are computed in argon and air flow fields. A single particle simulations and multiple particles simulations are performed and studied. The results show that the carbon vapor released by spalled particles tend to change the composition of the flow field, particularly the upstream region of the shock.

Hybrid Metal Oxide Cycle Water Splitting, Richard B. Diver Jr, Robert D. Palumbo, Nathan P. Siegel, James E. Miller

Other Faculty Research and Publications

Hybrid thermochemical water splitting cycles are provided in which thermally reduced metal oxides particles are used to displace some but not all of the electrical requirements in a water splitting electrolytic cell. In these hybrid cycles, the thermal reduction temperature is significantly reduced compared to two-step metal-oxide thermochemical cycles in which only thermal energy is required to produce hydrogen from water. Also, unlike the conventional higher temperature cycles where the reduction step must be carried out under reduced oxygen pressure, the reduction step in the proposed hybrid cycles can be carried out in air, allowing for thermal input by a …

High-Temperature, High-Pressure Viscosities And Densities Of Toluene, Aaron J. Rowane

Theses and Dissertations

High-temperature, high-pressure (HTHP) conditions are exemplified in ultra-deep petroleum reservoirs and can be exhibited within diesel engines. Accurate pure component hydrocarbon data is essential in understanding the overall behavior of petroleum and diesel fuel at these conditions. The present study focuses on the HTHP properties of toluene since this hydrocarbon is frequently used to increase the octane rating of gasoline and toluene occurs naturally in crude oil. In this thesis experimental densities and viscosity are presented to 535 K and 300 MPa extending the database of toluene viscosity data to higher temperature than previous studies. The data is correlated to …

Bioluminescent Magnetic Nanoparticles As Potential Imaging Agents For Mammalian Spermatozoa, Erick Salvador Vasquez, Jean M. Feugang, Scott T. Willard, Peter L. Ryan, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Background: Nanoparticles have emerged as key materials for developing applications in nanomedicine, nanobiotechnology, bioimaging and theranostics. Existing bioimaging technologies include bioluminescent resonance energy transfer-conjugated quantum dots (BRET-QDs). Despite the current use of BRET-QDs for bioimaging, there are strong concerns about QD nanocomposites containing cadmium which exhibits potential cellular toxicity.

Results: In this study, bioluminescent composites comprised of magnetic nanoparticles and firefly luciferase (Photinus pyralis) are examined as potential light-emitting agents for imaging, detection, and tracking mammalian spermatozoa. Characterization was carried out using infrared spectroscopy, TEM and cryo-TEM imaging, and ζ-potential measurements to demonstrate the successful preparation of these nanocomposites. Binding …

Prediction Of Vapor/Liquid Equilibrium Behavior From Quantum Mechanical Data, Marshall J. Gnap

Williams Honors College, Honors Research Projects

MOSCED (Modified Separation of Cohesive Energy Density) is a particularly attractive model for activity coefficients because it offers intuitive insights into how to tune solvent-solute interactions to achieve optimized formulations. Unfortunately, only 133 compounds have been characterized with the MOSCED method. Furthermore, there is no convenient method for extending MOSCED predictions to new compounds. The hypothesis of the present research is that the surface charge density of a molecule, once normalized over the molecule surface area, provided graphically by a σ-profile from density functional theory (DFT) computations, can be used to estimate the parameters used in the MOSCED model. DFT …

Unique Characterization Of Materials With Memory, John Murrough Golden

Articles

In general, materials with linear memory constitutive relations are characterized by a relaxation function. This leads to a situation where the free energy for most materials with memory is not unique. There is a convex set of free energy functionals with a minimum and a maximum element. An alternative procedure is proposed which characterizes a material by the kernel of the rate of dissipation functional. Using some recent results, we find that a unique free energy and relaxation function may then be deduced. An example is given for discrete spectrum materials. Also, the new results are used to show that …

Characterization Of Iron Phthalocyanine As The Cathode Active Material For Lithium-Ion Batteries, Sarwan S. Sandhu, Joseph P. Fellner

Chemical and Materials Engineering Faculty Publications

The developed thermodynamic functions for the determination of Gibbs free energy, enthalpy, and entropy of formation of solid lithium-iron phthalocyanine (LixFePc) from solid lithium and iron phthalocyanine as a function of x, defined as g-moles of the intercalated lithium per g-mole of iron phthalocyanine, at a fixed set of temperature and pressure conditions are presented. In addition, a proposed expression for the evaluation of lithium diffusion coefficient in solid iron phthalocyanine as a function of both x and temperature, and the experimental results from the ongoing research/development work on the lithium/iron phthalocyanine cells are included.

Thermodynamic Analysis Of Phenylpropanoid Pathway In Arabidopsis Thanliana, Patrick J. Ioerger, Rohit Jaini, John A. Morgan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Biofuels represent a renewable alternative to traditional fossil fuels. As dependence on fossil fuels rise so does the importance of improving the production of alternative fuels. Lignin poses one obstacle in the development of such alternative fuels. Its presence strengthens cell walls and hinders degradation of polysaccharides into monosaccharides, increasing cost and time while decreasing efficiency of the process. Lignin is composed of three monolignols, each of which is produced through the Phenylpropanoid pathway; a series of chemical reactions. This work aims to determine which reactions in the pathway are least thermodynamically favorable and thus most limiting. From metabolic mapping …